Process for the conversion of hydrocarbon oils



y 1934- J. F. DONNELLY 1,957,946

PROCESS FOR THE CONVERSION OF HYDROCARBON OILS Filed April 24. 1926 3Sheets-Sheet 1 y 8, 1934- J. F. DONNELLY 1,957,946

PROCESS FOR THE-CONVERSION OF HYDROCARBON OILS y 1934- J F. DONNELLY1,957,946

PROCESS FOR THE CONVERSION OF HYDROCARBON OILS Filed April 24, 1926 3Sheets-Sheet 3 Patented May '8, 1934 PATENT OFFICE PROCESS FOR THECONVERSION OF HYDROCARBON OILS 1 Joseph F. Donnelly, Lemont, Ill.,'assignor to I 'Donnelly Process Corporation, Chicago, 111., a

corporation of Nevada Application April 24, 1926,'Serial No. 104,365

12 Claims. 196-58) Thisinvention relates to a process for the conversionof heavy hydrocarbon oils into lighter hydrocarbon oils, and the presentapplication is a continuation as to common subject matter of myco-pending application (Serial 751,250 filed Nov.

21, 1924, which has matured into Patent No. 1,712,-

789). The apparatus disclosed in this application is the subject matterof. a copending application Serial No. 104,364, filed April 24, 1926.

It is an object of my invention to effect the con version of the heavieroils in such a manner that the final products possess chemicalcharacteristics more nearly approximating those of the naturalhydrocarbon oils than have heretofore been produced by crackingprocesses.

Another object is to effect the'production of the desired lighter endproducts .without reducing the heavier products of conversion to theform of solid 'endproducts such as hard carbon or coke.

Another object is to separate the residue from the products which it isdesired to subject to the conversion cycle, and keep the residue inliquid solution by adding thereto lighter solvent oils in such quantityas will prevent the residue from beingreduced to solid end products suchas free carbon or coke.

Another object is to establish such physical'condition of operation thatthe formation of hard carbon and coke in the apparatus is avoided.Another object is to prevent excessive decomposition of the heavierconstituents which constitute marketable products, such as fuel oils,lubricating oils and waxes, while at the same time permitting suchdissociation as is necessary to efiect the production of the desiredlighter products.

Another object is to utilize the heat of the reaction products todistill a mass of crude oil in such a manner that'the products ofdistillation from said crude oil intermingle with the products of thecracking reaction and undergo treatment in the cycle of operationtherewith.

A further object is to control the temperature of the zones offractional condensation by a heat interchange between the vapors-it isdesired to condense and the cooler crude oil. I

A further object is to' blend selected lighter fractions of the crudeoil, which are separated by fractional distillation with the fresh oiland selected condensates of'the cracking reaction to 0 form the makeupof the cycle oil.

A further object is to maintain the oil. in the heating step of thecycle of treatment under a temperature and pressure for such a length oftime that the cracking reaction is carried up to the point of a rapidformation of solid end products, such as carbon and coke and forthwithchecking the cracking reaction. 7

Other objects and advantages of my process will appear hereinafter.

In order to render my invention clear, reference is had to theaccompanying drawings in which I disclose a preferred means of carryingout my process.

In the drawings Fig. 1 is an elevation partly in cross section of anapparatus for carrying out my process. I

Fig. 2 is a side elevation partly in cross section, showing a, portionof the expansion chamber and fluid-controlling valve of the apparatus.

Fig. 3 is a section taken on line 3-3 on Fig. 2.

Fig. 4 is a plan view taken on line 44 on Fig. 2, showing the valve bodyand connected nozzles.

1 is a pipe still having a continuous coil of pipe 2' therein in whichthe oil to be heated is subjected to the heating step of the cycle oftreatment. A pump 3 supplies the oil to the coil 2 through a connectedpipe 4. A gauge 5 indicates the pressure on the oil in said pipe. Theheated oil isdelivered fromthe coil 2 through a connected pipe 6 to anexpansion chamber 7. A fluid-controlling valve 8 is located between thepipe 6 and the expansion. ch'amber'7. The valve 8 is the subject of myco-pending application Serial #823,545 filed. Jan. 25, 1926. The valve 8is provided with a body member 9 having a chamber 10 therein, to whichis connected the pipe 6. A tubular member 11 forms the outlet from thechamber 10. The member 11 has a valve seat thereon at its inner end,upon which operates a valve head 12, which is actuated by a; stem 13adapted to receive an operating member at 14. The tubular member 11extendsthrough the body member 9 a portion thereof being threaded asshown at 15. Surrounding the projecting end of the member 11 is atubular jacket 16 having an enlarged portion 17 thereon, which isthreaded on the threaded portion of the member 11 and abuts the bodymember 9 of the valve 8. The enlarged portion 1'7 thus acts as a lockingmember to firmly hold the tubular member 11 in operative position in thebody 9 of the valve 8.

A bushing l8 .surrounds the stem 13 and forms.

a closure member between the chamber 10 and the packing chamber'of apacking box 19, which is an integral extension of the body 9'. Thepacking box 19 is provided with a compression member 20. The compressionmember 20'is-provided with a flange 21 through which pass a pair ofpillar posts 22 which aiethreaded as shown and carry nuts 23 which bearagainstthe fiange21 119 and hold the compression member 20 in thedesired adjusted position against the packing in the packing box 19. Thepillar posts 22 are removably attached to a packing box 19 and are heldin place therein by nuts 24. By removing the nuts 24 the entiremechanism attached to the pillar posts 22, including the valve head 12and stem 13, may be'removed from the body 9 as a unit. The chamber 10 inthe body member is formed by a transverse bore which is closed at oneend by a closure member 25 having a seat 26 thereon which contacts witha seat 27 on the body member 9. A gasket may be interposed between theseats 26 and 27, as shown. The end of the pipe 6 is formed so as to matewith the annular seat 28 on the body member 9 at the oposite end of thebore forming the chamber 10. A flange 29 is attached to the pipe 6 andthe closure member 25 is formed with a flange 30. Bolts 31 passthroughopenings in the flanges 29 and 30 and are provided with nuts 32. Bymeans of these bolts and nuts the pipe 6 and the closure member 25 aredrawn toward each other, thereby holding them firmly in fluid tightcontact with the body member 9. The body member 9 has a passage 33therein leading to an annular recess 34 in the em larged portion 17 ofthe member 16. Passages 35 lead from the annular recess 34 into achamber 36, which opens into the annular space 37 between the member 11and the jacket 16. The

expansion chamber 7 is provided with a partition 38 in the center ofwhich is mounted a tubular member 39. The tubular member 39 extends overa portion of the jacket 16 and member 11, as shown in Fig. 2. Theexpansion chamber 7 is provided with a flange 40 which is bolted to aflange 41 secured to the body member 9. By this construction a chamber42 is formed in the expansion chamber 7 between the partition 38 andflange 41. Attached to the expansion chamber 7 and leading into thechamber 42 is an oil conducting pipe 43 which leads to the base of atower 44. In the present form of apparatus the expansion chamber 7 isformed with a restricted portion which passes through the wall of thetower 44 and an enlarged portion which is located within the base of thetower 44 and extends to a point near the bottom thereof, as clearlyshown in Fig. 1. The chamber 7 is provided with a series of outlet pipes45 at the lower ends thereof, which have downwardly extending ends. Thelower end of the chamber 7 is provided with a flange 46 to which isattached a plate 47, so positioned with respect to the flange 47 as toleave a space therebetween so as to form a circular outlet at rightangles to the chamber 7. The discharge of the streams of fluid throughthe annular outlet and downwardly extending ends of the pipes 45 iscaused by this construction to meet at right angles, thereby preventinga surging action which would arise by reason of the discharging streamsof fluid striking against the side walls of the tower.

The tower 44 is constructed so asto provide a series of zones ofdecreasing temperature adapted to subject the vapors therein tofractional condensation and provide a distilling section in the basethereof. The products of conversion are first passed into the base ofthe tower 44 which is normally filled to the desired level with residueoil. The level of the liquid in the base is indicated by a dotted lineon Fig. 1. A jacket of heat insulating material 48, surrounds the baseof the tower and is co-extensive with the level of the liquid in saidbase. The level of the liquid in the base is determined by a gauge 49which is provided with a series of try-cocks 50. A series of condensingbafiie plates 51 are located above the liquid in the base. The vaporswhich pass the bafiies 51 pass upwardly through a trap 52 which iscomposed of an annular plate 53, having acentral opening therethrough,over which a drum 54 is mounted. A plate 55 closes the upper end of thedrum 54. The drum 54 is provided with a series of openings 56 throughwhich the uncondensed vapors pass into a second zone of lowertemperature within the tower. Within this second zone is mounted aseries of condensing bafile plates 57. From this second zone theuncondensed vapors pass into a third zone of lower temperature through atrap 58 similar in construction to the trap 52. Within this third zoneis located a series of condensing baflie plates 59. Above the bafileplates 59 is located a tubular condenser 60 which is provided with asupply of cooling water through an inlet pipe 61. A water outlet pipe isprovided at 62. The uncondensed vapors which pass through the condenser60 are conducted through a pipe 63 to a coil in a cooling box 64 andfrom thence through a pipe 65 into a rundown tank 66. The condensateswhich are delivered to the tank 66 constitute a final end product suchas gasoline.

For the purpose of treating crude oil simultaneously with the crackedproducts a heat interchange is caused to take place between the crackedproducts and crude oil in such a manner that the crude oil acts as atemperature regulator for the zones of reactional condensation and atsame time is subjected to fractional distillation, The liquid andvaporous products of the fractional distillation of the crude oil arecaused to blend with the liquid and vaporous products of the crackingreaction and undergo treatment with them. To this end I have provideda'jacket 67 around the shell of the tower opposite the location of thethird zone' of lower temperature into which I introduce crude oilthrough a pipe 68. The level of the crude oil is allowed to rise to apredetermined height in the jacket-67, which is determined by anoverflow pipe 69 which leads to a jacket 70 around the shell of thetower opposite the location of the second zone of lower temperature. Thelevel of the oil in the jacket 70 is determined by an overflow pipe 71which leads to the base of the tower at 72 and also through a branchpipe 73 into the vapor space above the liquid in said base. The overflowpipes 69 and 71 are provided with downwardly extending legs as shown,and also with vents at 74 to prevent siphonic action. Overflow pipes 75and 76 provided with vents 77 are connected to traps 58 and 52 and areprovided with control valves 78 and 79. These overflow pipes dischargeinto a common pipe 89, which leads to a coil in a cooling box 81, fromwhence a pipe 82 leads to branch pipes 83 and 84, discharging into tanks85 and 86. The tanks 85 and 86 are provided with auxiliary inlets 87 and88 by which the tanks may be supplied with oil from an outside sourcewhen desired. The upper portion of jackets 67 and 70 constitute vaporspaces in which collect the vapors from the heated oil' in said jackets.The vapors thus produced are permitted to pass from the jackets 67 and'70 into the interior of the tower through openings 89 and 90 in thewalls of the tower. These vapors blend with the vapors of the crackingreaction and undergo treatment therewith.

The temperature of the third zone is maintained at such a degree thatthe condensates which collect in the trap 58 are of the kerosene series.The temperature maintained in the second zone is such that thecondensates collected in the trap 52 answer to the specifications of gas.oil. The first zone including-the base is maintained at such atemperature that the oil collected therein answers to the specificationsof fuel oil.- It will be understood that while I have designated oilssuch as gasoline, kerosene, gas oil and fuel oil, as produced in theseveral zones men-' tioned,- other fractions may be produced whendesired by suitable regulation of the temperature in said zones.

When it is desired to use a kerosene as the cracking stock the cycle oilis drawn from' the trap 58 by the pipe 91, which connects with the pipe92 leading to the inlet of the pump 8. The pipe 91 has a valve 93therein. Pipe 92 leads to the trap 52 and has a valve 94 therein. Whenoperating on kerosene as a cracking stock, the valve 93 in pipe 91 isopen, and the valve 94 in pipe 92 is closed. At this time the valve '78in pipe '75 is closed, and the valve '79 in pipe '76 isopen. A controlvalve in the branch pipe 83 is closed at this time and a control valvein the branch pipe 84 is open, allowing the gas oil from trap 52 to passinto the tank 86.

When it is desired to operate on gas oil as a cracking stock the cycleoil is drawn from trap 52 by way of pipe 92 and is fed to'the inlet ofpump 3. When operating in thismanner the valve 93 in pipe 91 is closed,and the valve 94 inpipe 92 is.

open. At the same time valve 79 in pipe '76 is closed, and valve '78 inpipe is open. Also the control valve in branch pipe 84 is closed and thecontrol valve in branch pipe 83 is open, allowing the kerosene from trap58 to pass to the tank 85. Separate valve controlled outlets 95 and 96lead from the tanks and 86 which connect with the pipe 9'7 leading tothe inlet of a pump 98. 'A pipe 99 connects the outlet of the pump 98with acoil 100, located in a receptacle 101, through which flowsthe hotresidue oil from the base of the tower 44 by way of a pipe 102. Thereceptacle 101 is provided with anoutlet 103. From the coil 100 the oil,which has been pre-heated by a heat interchange with the hot residue oilfrom the base of the tower, flows through avalve controlled pipe 104into a coil 105 located in the base of the tower 44 where it absorbsheat from the residue oil in the base of the tower. From the coil 105heated oil passes upwardly through a pipe 106, from which it maydischarge through a valve controlled branch pipe 107 into the trap 52 orthrough a valve controlled branch pipe 108 into the trap 58. Leadingfrom the pipe 104 is a pipe 109 having a control valve 110therein andconnected to said pipe 109 is a branch pipe 111 having a control valvel12.therein. The oil leaving the coil 100 may be wholly or partiallypassed through the pipe 109 or wholly or partially passed through thepipe 104 by a regulation of the controlling valves in these pipes. Byregulating valve 110' in pipe 109 and valve 112 in branch pipe 111 theoilfrom pipe 109 may be passed either into the trap 58 or the trap 52.When kerosene is being used as a cracking stock it may be drawn from thetank 85 and supplied to the pump 98 which forces it through the pipe 109into the trap 58, at which time the valve 110 is open and the valve 112is closed. When the gas oil is being used as a cracking stock it may bedrawn from the tank 86 and supplied to the pump 98, which forces itthrough the pipe 109- into the trap 52, at which time the valve 112 willbe open and the valve 110 closed.

In practice the apparatus is so proportioned as to extract fromthe crudeoil treated suflicient cracking stock such as kerosene or gas oil tosupply the cracking operation. If, due to certain conditions ofoperation or the nature of the crude oil treated, it is found that thenecessary amount of cracking stock maynot be extracted from the crudebeing treated, the necessary additional amount of such cracking stockmay be drawn from the tanks 85 and 86 which are furnished with anauxiliary supply through the inlets 8'7 and 88.

A valve controlled outlet pipe 113 is connected to the trap 52 whichallows a regulated quantity of the condensates to fiow from the trap 52into the base of the tower where they first come in contact with thevapors rising from the oil in the base and then descend in the cascadefashion over the plates 51 and finally blend with the oil in the base,acting as a temperature regulator and also as a solvent to keep theresidue oil in the base from being reduced to a condition whereby solidend products are formed, such as coke and free carbon. Thetemperature'of these condensates and rising vapors may be furthercontrolled by a cooling jacket 114, which may be furnished with coolingwater or other cooling agent such as oil if desired. The jacket 114 isprovided with inlet and outlet piping for the cooling agent, as shown.The temperature of the residue oil is further controlled by the heatinterchange taking place between the residue oil in the base and the oilpassing through the coil 105. Temperature indicators, such asthermometers or thermocouples 115,

are placed in position; where it is desirable to ob- .the traps 52 and58, from which it is fed through the pipes 91 and 92 into the inlet ofthe pump 3 which forces the oil through the heating coil and pipe 6 intothe expansion chamber '7, from whence it is delivered into the base'of'the tower 44 and fills the same up to the desired level, asindicated by the dotted line in Fig. 1. The level in the base may bedetermined at any,time by the gauge 49. During this preliminary fillingoperation the valves '78 and '79 in pipes '75 and '76 are closed. Whenthe desired level of the oil in the apparatus as indicated by the dottedlines in Fig.1, is reached the circulation of the oil from the tanks 85and 86, as the case may be, is discontinued and the valve in the by-pass116 is opened. The oil in the base is then passed by way of pipe 102receptacle 101 and by-pass 116 to the inlet of the pump 3, by which itis passed through the coil 2 and pipe 6 to the v expansion chamber '7,from which it enters the base. During this preliminary circulation toand from the base, as described, the furnace in pipe still 1 is inoperation applying heat to the oil as it passes through the coil 2. Whenthe oil in the system has reached its normal operating temperature thevalve and the by-pass 116' is closed, and thereafter during normaloperation the supply to the pump 3 is drawn from the traps 52 and 58, asthe case may be. Liquid level gauges 117 are provided as shown, whichindicate the liquid level in the traps 52 and 58.

The oil leaving the pipe 6, at approximately 900 F. under the regulationof-the controlling valve 8, passes through the tubular member 11, and isreleased at the outer end thereof into the tubular member 39 where itenters a zone of lower pressure and forms an expanding fluid jet in theouter portion of the member 39. This jet action creates a suction on theoil in the chamber 42 drawing it into the tubular member 39 anddischarging it with the heated expanding oil, into the expansion chamber7. The oil delivered from the chamber 42 is cooler than the heated oildischarged from the tubular member 11 which is at a cracking temperatureand acts to check the cracking reaction of the heated oil which isdischarged into expansion chamber 7 in such a manner that the crackingreaction does not proceed beyond the limits where a further crackingreaction would be productive of solid end products, such as free carbonand coke. The cracking reaction is also checked in this manner beforetotal decomposition is effected in the marketable products such as thelubricating and wax constituents thereof. I found that lubricating oilsand waxes are formed in the zone of lower pressure synthetically bypolymerization. In order to protect the oil in the chamber 42 fromhaving direct contact with the heated tubular member 11, steam is fedthrough a pipe 118 into the passage 33 and recess 34, from whence itflows through the passage 35 into the chamber 36 and annular space 37between the tubular jacket 16 and the tubular member 11. In this mannersolid deposits of carbon or coke on the tubular member 11, which mightotherwise be caused by local overheating, are avoided. The steam willalso assist thereafter in the fractional distillation. The cooler oilfrom the chamber 42 will, in addition to checking the cracking reactionwithin the chamber '7, act to control the amount of vaporizationeffected therein, and thereby retain a larger proportion of the highlyvolatile oils in the liquid form and also reduce the tendency toward theformation of gases. The lighter oils, which are thus kept in the liquidphase, have a solvent action, which also acts to prevent the formationof solid end products. The temperature of the residue oil is maintainedat such a point as to prevent total decomposition therein with theconsequent formation of solid end products.- The lighter oils also actto keep the heavier hydrocarbon constituents in liquid solution. Inaddition, solvent oil may also be drawn from the trap 52 and passed intothe residue oil in the base by means of the valve controlled pipe 113.

The crude oil, which is supplied through pipe 68 into the jacket 67, isstripped of its lighter fractions by vaporization which pass into thetower through the openings 89 and blend with the vapors passing into thecondenser 60. The remaining fractions of the crude then pass through theoverflow pipe 69 into the jacket '70 wherein a further distillation at ahigher temperature takes place, the vapors thus produced in the jackets'70 passing through the openings 90 into the tower and blending with thevapors passing through the openings 56 into the zone' above the trap 58,wherein the kerosene fractions are extracted. Theunvaporized oil in thejacket '70 passes through the overflow '71 and may be led through eitheror both of the valve controlled pipes 72 and '73 into the base of thetower, whereby such oil may be directly blended with the residue oil inthe base through the pipe '72 or passed in heat interchanging contactwith the vapors arising from the residue oil through the pipe '73. Thegas oil fractions of the oil thus introduced into the base from thejacket '70, are vaporized and blended with the vapors passing throughthe openings 56 in the trap 52 into the zone above the trap 52, whereinthe gas oil fractions are condensed.

In carrying out my process in a typical run on a characteristicMid-Continent gas oil of the following specificationsBaum gravity 34initial boiling point 405 F.maximum boiling point 780 F., a single passthrough the coil 2 of the cracking stock resulted in a product having aninitial boiling point of 75 F. and contained fractions vaporizingbetween 75 F. and 374 F. as tested by the Bureau of Mines method. Thisresult was obtained without the formation of a deposit of solid endproducts, such as free carbon and coke. The pressure carried on theheating coil 2 throughout the run was 1050 pounds per square inch, andthe temperature at the delivery end of the coil 2 was 890 F. By carefultests I have determined that the percentage of conversion of the heavyoils into lighter oils may be carried to 20 per cent and upwards withoutformation of solid end products such as free carbon and coke. It will beunderstood, however, that these percentages may vary with oils ofdifferent characteristics.

From the foregoing description it will be seen that my process providesa method of combined topping and cracking, wherein the vaporizationincident to the topping is effected by heat interchange with the heatedproducts of the cracking reaction and the vapors of the topping reactionundergo fractional condensation with the vapors of the crackingreaction. The cracking stock is madeup in part of freshly produced cleancondensates of the vapors of the cracking reaction, and also freshlyproduced oil extracted from the crude oil by fractional distillation andcondensation, which is effected simultaneously with and jointly treatedwith the products of the cracking reaction. It will be seen that thecracking stock, which is recycled to the action of the heating step ofthe cycle is not intermingled with the residue oil and thereforeconstitutes what is known as clean stock which is particularly adaptedto a cracking reaction, wherein it is desired to avoid formation ofsolid end products.

It is within the scope of my invention to check the dissociation of theheated oil either before or after vaporization or simultaneouslytherewith. The checking of the dissociation by reduction in temperaturemay take place upon the introduction of the heated oil into the base ofthe tower 44 upon coming in contact with the cooler oil in said base, inwhich case the prior step of cooling may be omitted. The temperature ofthe oil in the base would, under these circumstances, be controlled soas to accomplish the functions of checking the dissociation of the heavyoil and also the prevention of the formation of solid end products suchried under pressure directly up to its introduction bon oils whichconsists in heating a mass of relatively heavy hydro-carbon oil to acracking temperature under a pressure sufflcient to prevent vaporizationthereof, discharging said heated oil into a zone of lower pressure,simultaneously introducing a regulated quantity of relatively coolerhydrocarbon oil into said heated oil, introducing the products thusformed in said zone into a mass of hydro-carbon oil cooler than saidproducts, introducing a separate mass of relatively heavy hydro-carbonoil into said mass of cooler oil, subjecting the vaporized anduncondensed products to fractional condensation,introducing a portion ofthe condensates of said fractional condensation into said mixture ofcooler oil and separate mass of relatively heavy hydro-carbon oil,mixing a mass of fresh oil with a separate portion of the condensates ofsaid fractional condensation and subjecting the mixture of fresh oil andcondensates to the heating step of the cycle of treatment.

2. A process for the conversion of hydro-carbon oils which consists inheating a mass of relatively heavy hydro-carbon oil to a crackingtemperature under a pressure suficient to prevent vaporization thereof,discharging said heated oil into a zone of lower pressure, introducingthe products formed in said zone into a mass of cooler oil, introducinga separate mass of relatively heavy hydro-carbon oil into said mass ofcooler oil, subjecting the vaporized and uncondensed products thusformed to fractional condensation. introducing a portion of thecondensates of "said fractional condensation into the mixture of saidcooler oil and separatemass of relativelyheavy hydro-carbon oil,preheating a massof fresh oil by heat interchange with said mixture ofcooler oil, condensates and separate mass of relatively heavyhydro-carbon oil,- mixing said mass of preheated fresh oil with aseparate portion of the condensates of said fractional condensation andsubjecting said mixture of preheated fresh oil and condensates to theheating step of the cycle of treatment.

3. A process for the conversion of hydro-carhon oils which consists inheating a mass of relatively heavy hydro-carbon oil to a crackingtemperature under a pressure sufflcient to prevent vaporization thereof,discharging said heated oil into a zone of lower pressure,simultaneously introducing a regulated quantity of relatively coolerhydrocarbon oil into said heated oil, introducing the products thusformed in said zone into a mass of hydro-carbon oilcooler than saidproducts, subjecting the vaporized and uncondensed products thus formedto fractional condensation in a series of zones of decreasingtemperature, controlling the temperature of a zone of said series havinga relatively low temperature by heat interchange with a separated freshmass of crude oil so as to cause vaporization of the lighterconstituents thereof, mixing said vaporized lighter constituents withthe vapors undergoing condensation in said zone so as to undergotreatment therewith, passing theunvaporized fractions of said crude oilfrom said zone of relatively low temperature into heat interchangingrelation with a zone of relatively higher temperature of said series soas to control the temperature thereof and vaporize lighter constituentsof said unvaporized fractions of said crude oil, mixing the lighterfractions thus vaporized with the vapors undergoing condensation in saidzone of relatively higher temperature so as to undergo treatmenttherewith and passing the unvaporized fractions of said crude oil intoheat interchanging mixture with said vaporized and uncondensed productsseparated from said cooler oil in a zone of relatively highertemperature than the second. named zone of said series of zones.

4. A process for the conversion of hydrocarbon oils which consists inheating a mass of relatively heavy hydrocarbon oil to a crackingtemperature under a pressure sufiicient to prevent vaporization-thereof,discharging said heated oil into a zone of lower pressure,simultaneously introducing a regulated quantity of relatively coolerhydrocarbon oil into said heated oil, introducing the products thusformed in said zone into a mass of hydro-carbon oil cooler than saidproducts,-subjecting the vaporized and uncondensed products thus formedto fractional condensation in a series of zones of decreasingtemperature, controlling the temperature of a zone of said series havinga relatively low temperature by heat interchange with a separated freshmass of crude oil soas to cause vaporization of the lighter constituents4 tively higher temperature of said series so asto control thetemperature thereof and vaporize lighter constituents of saidunvaporizedfractions of said crude oil, mixing the lighter fractionsthus vaporized with the vapors undergoing condensation in said zone ofrelatively higher temperature, so as to undergo, treatment therewith,and passing the unvaporized fractions of said crude, oil into heatinterchanging mixture with said vaporized and uncondensed productsseparated from said cooler oil and directly with said cooler oil in azone of relatively higher temperature than the second named zone of saidseries of zones.

5. A process for the conversion of hydro-carbon ofls which consists inheating a mass of relatively heavy hydro-carbon oil to a crackingtemperature under a pressure suflicient to prevent vaporization thereof,discharging said heated oil into a zone of lower pressure,simultaneously introducing a regulated quantity of relatively coolerhydrocarbon oil into said heated oil, introducing the products thusformed in said zone into a mass of hydrocarbon oil cooler than saidproducts, subjecting the vaporized and uncondensed products thus formedto fractional condensation in a series of zones of decreasingtemperature, controlling the temperature of one of said zones by heatinterchange with .a separated fresh mass of crude oil in such a manneras to cause vaporization of lighter constituents thereof, mixing saidvaporized lighter constituents with the vapors undergoing condensationin said zone of said series so as to heavy hydro-carbon oil to acracking temperature under a pressure suilicient to prevent vaporizationthereof, discharging said heated oil into a zone of lowerpressure,introducing the products thus formed in said zone into a mass of hydro-150 carbon oil cooler than said products, subjecting the vaporized anduncondensed products thus formed to fractional condensation in a seriesof zones of decreasing temperature, controlling the temperature of azone of said series having a relatively low temperature by a heatinterchange with a separate mass of crude oil in such a manner as tocause vaporization of lighter constituents thereof, mixing saidvaporized lighter constituents with the vapors undergoing condensationin said zone of relatively low temperature so as to undergo treatmenttherewith, subjecting the condensates from said zone of relatively lowtemperature to the cracking step of the cycle of treatment, passing theunvaporized fractions of said crude oil from said zone of relatively lowtemperature into heat interchanging relation with a zone of relativelyhigher temperature of said series in such a manner as to control thetemperature thereof and vaporize lighter constituents of saidunvaporized fractions of said crude oil, mixing the lighter constituentsthus vaporized with the vapors undergoing condensation in said. zone ofrelatively higher temperature so as to undergo treatment therewith, andremoving the condensates from said zone of relatively higher temperature as an intermediate product.

7. A process for the conversion of hydro-carbon oils which consists inheating a mass of ,relatively heavy hydro-carbon oil to a crackingtemperature under a pressure sufiicient to prevent vaporization thereof,discharging said heated oil into a zone of lower pressure, introducingthe products thus formed in said zone into a mass of hydro-carbon oilcooler than said products, subjecting the vaporized and uncondensedproducts thus formed to fractional condensation in a series of zones ofdecreasing temperature, controlling the temperature of a zone of saidseries having a relatively low temperature by a heat interchange with aseparate mass of crude oil so as to cause vaporization of lighterconstituents thereof, mixing said vaporized lighter constituents withthe vapors undergoing condensation in said zone of relatively lowtemperature so as to undergo treatment therewith, removing thecondensates from said zone of relatively low temperature as anintermediate product, passing the unvaporized fractions of said crudeoil-from said zone of relatively low temperature into heat interchangingrelation with a zone of relatively higher temperature of said series insuch a manner as to control the temperature thereof and vaporize lighterconstituents of said unvaporized fractions of said crude oil, mixing thelighter constituents thus vaporized with the vapors undergoingcondensation in said zone of'relatively higher temperature so as toundergo treatment therewith, and subjecting the condensates from saidzone of relatively higher temperature to the cracking step of the cycleof treatment.

'8. A process forthe conversion of hydro-carbon oils which consists inheating-a mass of relatively heavy hydro-carbon oil to a crackingtemperature under a pressure sufficient to prevent vaporization thereof,discharging said heated oil into a zone of lower pressure, introducingthe products thus formed in said zone into a mass of hydro-carbon oilcooler than said products, subjecting the vaporized and uncondensedproducts thus formed to fractional condensation in a; series of zones ofdecreasing temperature, controlling thetemperature of a zone of saidseries having a relatively low temperature by a heat interchange with aseparate mass of crude oil so as to cause vaporization of lighterconstituents thereof, mixing said vaporized lighter constituents withthe vapors undergoing condensation in said zone of relatively lowtemperature so as to undergo treatment therewith, mixing a fresh mass ofoil with the condensates from said zone of relatively low temperature,subjecting the mixture thus formed to thecracking step of the cycle oftreatment, passingthe unvaporized fractions of said crude oil from saidzone of relatively low temperature into heat interchanging relation witha zone of relatively higher temperature of said series in such a manneras to control the temperature thereof and vaporize lighter constituentsof said unvaporized fractions of said crude oil, mixing the lighterconstituents thus vaporized with the vapors undergoing condensation insaid zone of relatively higher temperature so as to undergo treatmenttherewith and removing the condensates from said zone of relativelyhigher temperature as an intermediate product.

9. A process for the conversion of hydro-carbon oils which consists inheating a mass of relatively heavy hydro-carbon oil to a crackingtemperature under a pressure sufficient to prevent vaporization thereof,discharging said heated oil into a zone of lower pressure, introducingthe products thus formed in said zone into a mass of hydro-carbon oilcooler than said products, subjecting the vaporized and uncondensedproducts thus formed to fractional condensation in a series of zones ofdecreasing temperature, controlling the temperature of a zone of saidseries having a relatively low temperature by a heat interchange withaseparate mass of crude oil so as to cause vaporization of lighterconstituents thereof, mixing said vaporized lighter constituents withthe vapors undergoing condensation in said zone of relatively lowtemperature so as to undergo treatment therewith, removing thecondensates from said zone of relatively low temperature as anintermediate product, passing the unvaporized fractions of said crudeoil from said zone of relatively low temperature into heat interchangingrelation with a zone of relatively higher temperature of said series insuch a manner as to control the temperature thereof and vaporize lighterconstituents of said unvaporized fractions of said crude oil, mixing thelighter constituents thus vaporized with the vapors undergoingcondensation in said zone of relatively higher temperature so as toundergo treatment therewith, mixing a fresh mass of oil with'thecondensates from said zone of relatively higher temperature andsubjecting the mixture thus formed to the cracking step of the cycle oftreatment.

10. A process for the conversion of hydrocarbon oils which consists ofheating a mass of relatively heavy hydrocarbon oil to a crackingtemperature under a pressure sufficient to prevent vaporization thereof,discharging said heated oil into a zone of lower pressure, introducingthe products thus formed in said zone into a mass of hydro-carbon oilcooler than said products, subjecting the vaporized and uncondensedproducts thus formed to fractional condensation in a series of zones ofdecreasing temperatures, controlling the temperature of a zone of saidseries having a relatively low temperature by a heat interchange with aseparate mass of crude oil so as to cause vaporization of lighterconstituents thereof, mixing said vaporized lighter constituents, withthe vapors undergoing condensation in said zone of relatively lowtemperature so as temperature into a to undergo treatment'therewith,preheating a fresh mass of oil by a heat mass of oil cooler than saidproducts and mixing it with the condensates from said zone of relativelylow temperature, subjecting the mixture thus formed to the cracking stepof the cycle of treatment, passing the unvaporized fractions of saidcrude oil from said zone of relatively low heat interchanging relationwith a zone of relatively higher temperature of said series insuch amanner as to control the temperature thereof and vaporize lighterconstituents of said unvaporized fractions of said crude oil, mixing thelighter constituents thus vaporized with the vapors undergoingcondensation in'said zone of relatively higher temperature so as toundergo treatment therewith and removing the condensates from said zoneof relatively higher temperature as an intermediate product.

' vent vaporization thereof;

11. A process for the conversion of hydrocarbon oils which consists inheating a mass of relatively heavy hydrocarbon oil to 'a crackingtemperature under a pressure sufficient to predischarging said heatedoil into a zone of lower pressure, introducing the products thus formedin said zone into a mass of hydro-carbon oil cooler than said products,subjecting the vaporized and uncondensed products thus formed tofractional condensation in a series of zones of decreasing temperature,controlling the temperature or a zone of said series having a relativelylow temperature by a heat interchange with a separate mass of crude oilso a to cause vaporization of lighter constituents thereof, mixing saidvaporized lighter constituents with the vapors undergoing condensationin said zone of relatively low temperature so as to undergo treatmenttherewith, removing the condensates from said zone of relatively lowteminterchange with said' perature as an intermediate product, passingthe unvaporized fractionspf said crudeoil from said zone of relativelylow temperature into heat interchanging relation with a zone ofrelatively higher temperature of said series in such a manner as tocontrol the temperature thereof and vaporize lighter constituents ofsaid unvaporized fractions of said crude oil, mixing the lighterconstituents thus vaporized with the vapors undergoing condensation insaid zone of relatively higher temperature so as to undergo treatmenttherewith, preheating a fresh mass of oil by heat interchange with saidmass of oil cooler than said products and mixing it with the condensatesfrom said zone of relatively higher temperature and subjecting themixture thus formed to the cracking step of the cycle of treatment.

12. A process for the conversion of hydrocarbon oils which consists inheating'a mass of relatively heavy hydrocarbon oil to a crackingtemperature between 7700 and 1000" F. under a pressure from 600 to 2000pounds per square inch for a sufllcient length of time to convert in asingle exposure to said temperature and pressure 20 percent and upwardsinto lighter oil, forthwith checking the dissociation of said heated oilby reducing the temperature thereof in such a manner as to inhibit theformation of free carbon therein, introducing the products of conversioninto a mass of oil cooler than said products,

subjecting the uncondensed and vaporized products thus formed tofractional condensation, returning a portion of the condensates of saidfractional condensation to said mass of cooler oil, mixing a mass offresh tion of said condensates and subjecting said mixture of fresh oiland condensates to the heating step of the cycle of treatment.

JOSEPH F. DONNELLY.

oil with a separate por- H

